What are the pressure control methods for the tower top reflux drum? Are there any selection criteria?
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This post was last edited by libingtaoff8 on 2017-5-30 at 13:05. The reflux tank at the top of the tower can be controlled using nitrogen and venting, as well as by the gas supplied from outside; it can also be controlled with non-condensable gases. Is that all you know? Are there any other control methods? What determines the selection of these pressure controls?
Summarize operational experience based on the process conditions
Most systems use stage control, meaning that any excess gas at the top of the nitrogen pressure-boosting tower is directly vented; under normal conditions, nitrogen is not used at all, and its role is merely to establish the pressure in the distillation system during startup. Normally, a unidirectional control valve is used for cascade control: discharge occurs when the pressure is high, and discharge is reduced when the pressure is low
Divided into control: pure pressure control~~~
Since nitrogen sealing increases the nitrogen content in gasoline, most systems now use fuel gas or hydrogen for sealing. Fuel gas is used at low pressure, while hydrogen is used at higher pressures. The pressure at the top of the tower is generally controlled by the gas flow rate at that location!
This post was last edited by 佾窗侃砜憬╰℡ on 2017-6-14 at 19:21. Nitrogen and oil simply don’t meet the conditions for a reaction; so how can the nitrogen content increase? ? Molecular nitrogen has little impact on processes such as hydrogenation; therefore, I believe the reason you mentioned is incorrect. The main reason for using fuel gas or hydrogen as sealing gas is that sealing gas is generally sent to low-wattage pipelines, and using nitrogen would hinder the recovery or combustion of low-wattage energy
Although the reaction conditions are not met, when gas is mixed with oil, some of the gas always dissolves in the oil, albeit in an inorganic form. When a torch is burning, fuel gas is always used as an auxiliary fuel; as long as a large amount of nitrogen does not enter, it generally has no impact on the torch’s combustion.
Molecular nitrogen should have no effect on the reaction; nitrogen sealing is feasible, but it is generally not used probably because it reduces the content of low-wattage nitrogen gas
It is generally controlled in stages; nitrogen or gas is used as the sealing medium. During normal operation, the automatic mode is employed – air is added when the pressure is low and air is released when the pressure is high. However, since this leads to waste of nitrogen or gas, both the inlet and outlet have been modified to use two separate control circuits: the inlet pressure is kept at a lower level while the outlet pressure is kept at a higher level. In this way, as long as the pressure inside the container remains constant, the valves do not need to be opened or closed frequently.